(By way of quick explanation to the layman, there are three kinds of nameservers that affect your life:

Root nameservers: which top level domain registries operate, such as the root nameservers for .com or .ca

Authoritative nameservers: for individual domains. This is the business easyDNS is in: answering DNS queries authoritatively for its member domains.

Recursive nameservers or resolvers: these nameservers find out DNS info on behalf of its users. Usually these are transparent to end-users and supplied by ISPs, often via DHCP. OpenDNS is now in this business. )